Engineer questions government wind turbine sound testing methods
By Barb McKay
An acoustics engineer is questioning the Ontario government’s methods for setting baseline sound limits for wind turbines after field testing was recently conducted in Kincardine.
Todd Busch, project manager for Swallow Acoustic Consultants Ltd., was in front of the Municipality of Kincardine council during its meeting last Wednesday to go over data from a study conducted within the boundaries of the Armow Wind Project last fall. Swallow was contracted by the municipality to study baseline acoustic and infrasound levels prior to the 92-turbine, 180-megawatt project becoming operational.
Engineers conducted interior and exterior sound testing at five homes within the project area between Oct. 30 and Nov. 14, 2015, using special microphones designed specifically to record infrasound (sound not picked up by the human ear). The sound measurements account for sound levels from wind in exterior testing.
Busch said when a noise impact study was conducted with audible sound testing for Armow Wind in 2013, engineers who did the study declared that the project would comply with Ontario Ministry of the Environment noise limits for industrial wind turbines. He said the study was done using an average wind speed at a particularly quiet site and a measurement of seven decibels was added to factor in sound levels at a higher wind speed. In the noise impact assessment summary, Busch said sound levels were calculated at between 37 and 39.8 decibels. The noise level limit set by the province is 40 decibels. Infrasound levels were not tested.